Polypropylenes are useful in a number of everyday articles such as, for example, storage containers, pails, and ice cream containers. However, one drawback to the use of polypropylene homopolymers and/or random polypropylene copolymers (RCP) in such end use applications is their relatively high glass transition temperature, approximately about 0° C. Such relatively high glass transition temperature renders these materials brittle, especially at sub-zero temperatures. RCP is typically the material of choice for injection molded clear containers. Due the inherent high crystallinity and high glass transition temperature of RCP, the injection molded articles made of RCP typically have poor impact strength; thus, requiring impact modification. For example, at low temperature ranges, for example less than approximately 0° C., the low impact strength of RCP injection molded articles typically causes significant product failure during the transportation and handling of the product. Addition of a plasticizer and/or elastomer, as one or more impact modifiers, to such materials is one way to improve such properties, e.g. impact strength and toughness. However, the addition of impact modifiers, the clarity of the molded articles may be severely compromised and can be very hazy. Traditionally, elastomers such as ethylene alpha-olefin-based impact modifiers used in clarity applications have a matching refractive index to the RCP and are limited to the range of 0.90 g/cc.
Despite the research efforts in improving the properties of such injection molded articles, there is still a need for composition providing both improved clarity and toughness of in injection molded articles.